Furnace



7 1,629 447 May 1927' 0. DE LORENZI FURNACE Filed Sept 4.- 1925 VENZ'OR B (p/aadfaiglwy A TT ORNE Y Patented May 17, 1927.

UNITED STATES OTTO DE LORENZI, OF MAPLEWOOD, NEW J E BUSTION ENGINEERING CORPORATION,

DELAWARE.

RSEY, ASSIGNOR T INTERNATIONAL COM- OF NEW YORK, N. Y., A CORPORATION OF FURNACE.

Application filed September 4, 1925. Serial 1T0. 54,404.

My invention relates to furnaces and has special reference to traveling grate furnaces of the type which are particularly adapted for use in burning coke breeze and other low 5 grade fuels.

Traveling grate furnaces of this type are commonly provided with both front and rear arches, the rear arch extending over approximately one-half of the length of the fuel supporting portion of the grate, an

being spaced from the front arch so as to provide a relatively narrow gaspass extending between the longitudinal side walls of the combustion chamber and leading to the boiler tubes. In traveling grate furnaces of this type as heretofore constructed, it has been found that there is a tendency of the gases of combustion in following the ath of least resistance to concentrate at the center of the gas pass leading to the boiler, and thus the greater portionthereof flow through the central portion of sai gas pass and the gas passes of the boiler, which of course is objectionable. Such central flow of the combustion gases in the prior constructions is particularly noticeable where the"gas passes of the boiler are of greater width than the combustion chamber of the furnace, as in such cases very little, if any, of the gases reach the side portions of the gas passes of the boiler. With traveling grate furnaces of this type as heretofore constructed, particularly where the boiler is of greater width than the combustion chamber of the furnace, it has been found that due to the tendency of the gases of combustion to follow the path of leastresistance, the greater portion of the gases tend to concentrate at and pass through the central portion of the gas passes of the boiler, a comparatively small part of the gases reaching the side portions of the gas passes, which of course is objectionable.

An object of the present invention is to provide a traveling grate furnace of the character indicated in which there is provision of means for insuring a more even distribution of the combustion gases throughout the width of the gas passes of the boiler. thus securing a more eflicient utilization of the heat of the gases.

Another object of the invention is to provide a novel and improvedfc'ombustion arch construction for a traveling grate stoker d the drawings, which which is particularly adapted for use in cases where the gas passes of the boiler are of greater width than the combustion chamber of the furnace.

Another object of the invention is to provide a novel and improved combustion chamber for a boiler furnace.

The several features of the invention, whereby the above mentioned and other obd jects maybe attained, will be clearly under- .stood from the following description and accompanying drawings, in which:

Figure 1 is a longitudinal sectional view of a traveling grate boiler furnace embodying the features of the invention in their preferred form, the section being taken substantially on the line 1-1 of Fig. 2; and

Fig. 2 is a detail sectional plan view, partly diagrammatical, taken on the line 2-2 of Fig. 1.

The traveling grate furnace illustrated in is particularly adapted for use in burning coke breeze and other low grade fuels, is provided with the usual chain grate 2, and combustion chamberhaving longitudinally extending side walls 4, front and rear walls 6 and 8, a front arch 10 and a rear arch 12. The rear arch extends over approximately one-half the length of the fuel supporting portion of the grate and is spaced from the front arch 10 so as to provide a relatively narrow gas pass 14 extending between the side walls and leading to the tubes 16 of the boiler, the walls of the gas pass diverging upwardly to the boiler tubes.

In traveling grate furnaces of this type as heretofore constructed, the gas pass extending between the side walls has usually been of uniform width throughout its length, with the result that there is a tendency of the gases in following the path of least resistance to concentrate at the center of the gas pass, and thus the greater portion thereof flow through the central portion of said gas pass and the gas passesof the boiler, which of course is objectionable. Such central flow of the combustion gases is pa ticularly noticeable in cases where the boiler is of greater width than the combustion chamber of the furnace, as in such cases very little, if any, of the gases reach the side portions of the gas passes of the boiler.

To overcome such objectionable features of the prior constructions, in my approved furnace as illustrated in the drawings, the gas pass 14 between the front and rear arches of the combustion chamber diverges in Width from substantially its center toward its ends so that less restricted paths are provided for the flue gases adjacent the side walls of the furnace than near its cen ter, and it will be apparent by making such variation in the width of the gas pass of the proper proportion, that a substantially uniform distribution of the waste gases throughout the length of the gas pass may be secured. This construction is particularly advantageous in cases where the boiler is of greater width than the combustion chamber of the'furnace as it insures a material portion of the waste gases reaching the extremeside portions of the gas passes of the boiler. In the illustrated construction I have provided such variation in the width,

of the gas pass by providing the op osed walls of the front and reararches wit opposed stepped portions 18 substantially at he center thereof, opposed stepped onion 20 adjacent the side walls of the com ustion chamber, and opposed stepped portions 22 between the portions 18 and 20. I have found that satisfactory results may be secured in a furnace where heretofore the lower portion of the flue gas pass 14 has been of a width of substantially three feet throughout its length, by spacing the stepped portions 18 two feet six inches apart, the intermediate stepped portions 22' three feet apart, and the end stepped portions 20 three feet six inches apart, al

though it will be a parent that the propor-' tions may be varie I to meet different conditions. v

It. will be apparent that my improved construction not only insures a more uniform distribution of the gases throughout the gas passes of the boiler, but also insures a more thorough and uniform mixing of the gases within the combustion chamber.

As will be evident to those skilled in the art, my invention permits various modifications without departing from the spirit thereof or the scope of the appended claims. What I claim is: 1. A boiler furnace having a combustion chamber having longitudinally extending side walls, and a roof having a relatively narrow gas pass extending transversely thereof and leading to the boiler, and increasing in width from substantially its center toward said side walls.

2. A boiler furnace having a combustion chamber having longitudinally extending side walls, and a roof havinga relatively narrow gas pass extending transversely thereof, leading to the boiler, and being of greater width near its ends than near its center.

3. A furnace having, in combination, a traveling grate, a combustion chamber having longitudinally extending side walls arranged adjacent the longitudinal sides of said grate, front and rear arches extending over said grate and spaced apart with their opposed wall portions diverging from substantially their center toward said side walls to provide a gas ass increasing'in width from substantially its center toward its ends.

4. A furnace having, in combination, a traveling grate, a combustion chamber having longitudinally extending side walls arranged adjacent the longitudinal sides of said grate, and front and rear arches extending over said grate'and spaced apart with their opposed wall portions of stepped formation to provide a gas pass increasing in width from near its center toward its ends.

' 5..A boiler furnace having in combination, a traveling grate, a combustion chamber having longitudinally extending side walls arranged adjacent the longitudinal sides of said grate, a front arch, and a rear arch extending over substantially one-half of the length of the fuel supporting ortion of said grate and spaced from sai front arch so as to provide a narrow gas pass extending between said side walls and leading to the boiler, the walls of said gas pass diverging upwardly toward the boiler and the lower portion of the walls of said gas pass diverging from substantially their center toward said side walls.

In testimony whereof, I' have si ned my name to this specification this 2nd day of September, 1925.

OTTO DE LORENZI: 

